1973 DATSUN B110 oil change

AUTOMATIC

TRANSMISSION

Manual

linkage

The
hand
lever
motion

The
hand

lever
is
located

in
the
driver

s
com

part

men

mechanically
transmitted
from

the
remote
control

linkage
is
further

transmitted
to
the
inner
manual

lever

in

the
transmission

case
from
the

range

selector
lever
in

the

right
center

poc

tion

of
the

transmission
case

through

the
manual

shaft
The
inner

manual

lever
is

thereby
turned

A

pin
installed
on

the
bottom
of

the
inner
manual
lever
slides
the

manu

al

valve

spool
of
the

control
valve
and

thus
the

spool
is

appropriately
posi

lioned

opposing
to

each
select

position

The

parking
rod

pin
is

held
in
the

groove
on
the

top
of
the
inner

manual

plate
The

parking
rod

pin
operates
the

rod
at
p

range
and

operates
the

mechanical

lock

system

Moreover
the
above
described

manual
shaft
is

equipped
with
an

inhibitor
switch
A

rotor
inside
the

inhibitor
switch
rotates
in

response
to

each

range
When
the

range
is
selected

at
p
or
N
the

rotor
closes
the

starter

magnet
circuit
so
that
the

engine
can

be
started
When
the

range

is
selected

at
R
the

rotor
closes
the

back

up
lamp
circuit
and
the

back

up

lamp
lights

Vacuum

diaphragm

The
vacuum

diaphragm
is
installed

un
the
left

center

portion
of
the

transmission
case
The

internal
con

struction
of
the
vacuum

diaphragm
is

as
follows
A
rubber

diaphragm
forms

a

partition
in
the
center
The

engine

intake
manifold

negative
pressure
led

through
vacuum
tube
and

spring
force

are

applied
to
the
front
surface
of
the

rubber

diaphragm
and

atmospheric

pressure
is

applied
to
the
back
surface

A
difference
between
pressure

applied

to

the
front
and
back
surfaces
be

comes
a

vacuum
reaction
and
thus

the
throttle
valve
of
the

control
valve

inside
the
transmission
case
is

op

erated

When
accelerator

pedal
is

fully
de

pressed
and
the
carburetor
is

fully

upened
but
the

engine
speed
is
not
1

Housing

2
Cover

3

Outer
gear
AT071

4
Inner

gear

5
Crescent

Fig
AT
3
Oil

pump

1

Manual

plate

2

Inhibitor

switch
A
TOB7

3

Parking
rod

4
Manual

shaft

Fig
AT
4

Manuallinhage

To
intake
manifold

A

TOBB

Fig
A
T
5

Vacuum
diaphragm

iV

Down
shift
solenoid
i

KiCk
down

switch

A

TOB9

Fig
A
T
6

Downshift
solenoid

AT
5
sufficiently
increased
the
manifold

negative
pressure
lowers

becomes

similar
to
the

atmospheric
pressure

and
the

vacuum
reaction

increases

since

the
flow

velocity
of
mixture

inside
the
intake
manifold
is

slow

Contrarily
when
the

engine
speed

increases
and

the
flow

velocity
of

the

mixture

increases
or
when

the
carbure

tor
is
closed

the
manifold

negative

pressure
increases
becomes
similar
to

vacuum
and
the

vacuum
reaction

reduces

Thus
a

signal
to

generate
hydraulic

pressure
completely
suited
to

the

engine

loading
at
the

control
valve
is

transmitted
from

the
vacuum
dia

phragm
and

most
suitable

speed

change
timing
and
line

pressure
are

obtained
so

that
the
most

proper

torque
capacity
is

obtained

against
the

transmitting

torque

Downshift

solenoid

The
downshift

solenoid
is

of
a

magnetic
type
installed

on
the
left
rear

portion
of
the

transmiSsion
case

When

a

driver

requires
accelerating
power

and

depresses
the
accelerator

pedal

down
to

the

stopper
a

kick
down

switch

located
in
the

middle
of
the

accelerator
link
is

depressed
by
a

push

rod
the
kick
down
switch
closes
cur

rent
flows
to

the
solenoid
the
sole

noid

push
rod
is

depressed
the

down

shift
valve
of

the
control
valve
inside

the
transmission

case
is

depressed
and

the

speed
is

changed
forcedly
from

3rd
to
2nd
within
a

certain
vehi

cle

speed
limit

Note
As
the
kick
own

switch
closes

when
the
accelerator

pedal
is

depressed
from
7
8
to
IS
16
of

the
whole
stroke
the

accelera

tor

pedal
should
be

correctly

adjusted
and
fixed
so
as
to

afford

complete
stroke

The

arrangement
of
the
switch

differs

according
the
models
of

vehicle

Governor
valve

The

primary
and

secondary
gover

nor
valves
are
installed

separately
on

the

back
of
the
oil
distributor
on

the

I
transmission

output
shaft

They

op

erate
in
the
same

speed
as
that
of
the

output
shaft
In
other
wotds

they

operate
at

a

speed
in

proportion
to
the

vehicle

speed
To
those
valves
the

line

pressure
is

applied
as
the

input

ftom
the
control
valve

through
the

transmission
case
rear

flange
and
oil

distributor
The

governor
pressure
in

proportion
to
the

output
shaft

speed

vehicle

speed
is
led

to
the

shift

valve

of
the
control
valve

through

inverse

rou
te
as
the

output
and
thus

the

speed
change
and
the
line

pressure

are

controlled

Operation
of

secondary

governor
valve

The

secondary
valve
is
a
control

valve
which
receives

line

pressure
I

and

controls
the

governor
pressure

When
the
manual

valve
is

selected

D
2

or
1

range
line

pres

sure
is

applied
to
the

ring
shape
area
of

f
this

valve
from
circuit

I
and

this

valve
is

depressed
toward
the

center

side
Movement
of
this
valve
to
a

certain

position
closes
the
circuit

from

I
to

15

simultaneously
while
mak

ing
a

space
from
the

15
to
the
center

drain

port
and

pressure
in
the

circuit

IS
is

lowered

When

the
vehicle
is

stopped
and
the

centrifugal
force
of
this
valve
is
zero

the
valve
is

balanced
In
this
a

gover

nor

pressure
which
is
balanced
with

the

spring
force
occurs
on
the

15

When
the

vehicle
is

started
and
the

centrifugal
force
increases
this

valve

slightly
moves
to
the
outside
and

when

the

space
from

I
to
15

increases

space
from
the

15
to
the

drain

port
reduces

simultaneously
As

the
result

governor
pressure
of
the

15
increases

and
the

governor

pres

sure
is

balanced
with
the
sum
of

centrifugal
force
and
the

spring
force

The

governor

pressure
thus

changt
s
in

response
to
the

vehicle

speed

change

centrifugal
force

Operation
of

primary

governor

valve

The
valve
is

an
ON
OFF

valve

which
closes
the

governor

pressure

15

regulated
by
the

secondary

gover
CHASSIS

nor
valve
when
the
vehicle

speed

reaches
the

minimum

speed
and

when

the
vehicle

speed
exceeds
a
certain

level

open
the

governor
and
forwards

the

governor
pressure
15
to
the

control

valve

When
the

vehicle
is

stopped
the

governor

pressure
is

zero
However

when
the

vehicle
is

running
slowly

this
valve

is

depressed
to

the
center

side

and
the

groove
to

the

IS
is

closed
since
the

governor
pressure

applied
to
the

ring

shape
area
is

higher

than
the

centrifugal
force
of
this

valve

When
the

governor
speed
exceeds
cer

tain

revolution
the

governor

pressure

in
the
circuit
15
also

increases
How

ever
as
the

centrifugal
force
increases

and
exceeds

the

governor
pressure
this

valve

moves
toward
the
outside
and

the

governor
pressure
is
transmitted

to

the
circuit
15

Two
different

valves
are

employed

in
the

governor
so
that
it
will
inde

pendently
control

the

speed
at

high

speed
and
at

low

speed
That

is
within

the

low

speed

range
the

governor

pressure
is
not

generated
owing
to
the

primary
valve

whereas
at

the

high

speed
range
above
the

break

point
a

governor

pressure
regula
ted

by
the

sec0Hdary
valve
is

introduced

The
break

point
is
the

point
at

which
the

function
of
one

of
the

govp
rnors
is

transferred
to
the
other

whee

the

speed

changes
from

the

w

speed

range
to

the

high
speed

range

To
con
trol
valve

Governor

pressure

tiS

y
ID

t

4

From
control
valve

Line

pressure
I

J

I

Primary
governor

2
Secondar

governor

3
Governor
valve

body
AT090

4

Oil
distributor

5

Output
shaft

Fig
AT
7
Cross

sectional
view

of

governor

AT
6
AT091

Fig
A
T
B

Output
shaft
with
oil

distributor
and

governor

I
Oil

distributor

2

Governor
valve

body
AT092

3

Primary

governor

valve

4

Secondary

governor

valve

Fig
A

T

9

Exploded
uiew

of

gouernor

Control

valve

assembly
AUTOMATIC
TRANSMISSION

Oil

from

pump

ru
nn

i

I
I
I
Throttle
valve

I

I

1
m
nn

I
Auxiliary
valve

I
Regulator
valve

j

Manual
valve

I

Uoe

pressure

Speed
change
L

I
Governor

valve

I
I
valve

J
1
1

Clutch
and
brake

Flow

chart
of

control
valve

system

The
control
valve

assembly
receives

oil

from
the

pump
and
the

individual

signals
from
the
vacuum

diaphragm

and
transmits
the
individual

line

pres

sures
to
the
transmission
friction

ele

ment

torque
converter
circuit
and

lubricating
system
circuit

as
the
out

puts
To
be

more

specifically
the
oil

from
the
oil

pump
is

regulated
by
the

regulator
valve
and
line

pressures
build

up
The
line

pressures
are
fed
out
from

the
control
valve

assembly
as

they
are

through
various
direction

changeover

valves

including
ON
OFF
valve
and

regulator
valves

newly
reformed
to
a

throttle

system
oil

pressure
and

op

crates
other
valves

or

finally
the
line

pressure
are
transmitted
to

the
re

quired
clutch
or
brake
servo

piston

unit
in

response
to
the

individual

running
conditions
after

receiving
sig

nals
from
the

previously
described

vacuum
diaphragm
downshift
sole

noid

governor
valve

and
or

manual

linkage

The
control
valve

assembly
consists

of
the

following
valves

Pressure

regulator
valve

2
Manual
valve

3
1st

2nd
shift
valve
4

2nd
3rd
shift

valve

S

Pressure

modifier
valve

6

Yacuum
throttle
valve

7

Throttle
back

up
valve

8
Solenoid

downshift
valve

9
Second

lock
valve

0

2nd
3rd

timing
valve

Pressure

regulator
valve

PRV

The

pressure
regulator
valve

re

ceives

valve

spring
force
force
from

plug
created

by
the
throttle

pressure

16
and
line

pressure
7
and
force

of

the

throttle

pressure
18

With
the

mutual

operations
of
those
forces
the

PRY

regulates
the
line

pressure
7
to

the

most
suitable

pressures
at
the

individual

driving
conditions

The
oil
from
the
oil

pump
is

ap

plied
to
the

ring
shaped
area

through

orifice
20
As

the
result
the
PRY
is

depressed
downward
and

moves
from

port
7

up
to
such
extent
that
the

space
to
the

subsequent
drain

port

marked
with
x
in

Figure
AT
10

opens
slightly
Thus
the
line

pressure

7
is
balanced
with
the

spring
force

AT
7
and
the
PRY
is

thereby
balanced
In

this
the

space
from
the

port
7

to
the

subsequent
converter
oil

pressure
14

circuit

has
also
been

opened
As

the

result
the

converter
is
filled
with
the

pressurized
oil
in
the
circuit
14
and

the

oil
is

further
u
d

for
the

Iubrica

tion
of
the
rear
unit
Moreover

a

part

of
the
oil
is

branched
and

used
for
the

lubrication
of
front
unit

for
the
front

and
rear
clutches

When
the

accelerator

pedal
is
de

pressed
the
throttle

pressure
16
in

creases
as

described
in
the

preceding

paragraph
oil

pressure
is

applied
to

the

plug
through
orifice
21
and
the

pressure
is

added
to
the

spring
force

As
the

result
the
PRY
is

contrarily

depressed
upward
space
to
the
drain

port
is

reduced
and
the
line

pressure

7
increases

Afl

II

Jwi
06

A

J
L
I

7

I

tf

Iij

BL

i
il
J

jti
r

x

r
1
J

I

l

I

X

6

C

l
o

ii
J

f

A

T09S

Fig
AT
10
Pressure

regulator
value

tr
r

Low
in

the

range
I
is

led
to

the
low

and
reverse
clutch
from
the

line

pressure
5

through
the
line

pressure
12
and
at
the
same
time

the
same
is
led
to
the
left
end

spring

unit

Consequently
although
the

go

vernor

pressure
increases
the
valve
is

still

depressed
toward
the

right
and

the
SFV
is

fixed
in
the
Low

posi

tion
When

kicked
down

at
the

2nd

speed
the
SDV

operates
and
the

line

pressure
13
depresse
the
FSV
to

ward
the

right

Although
the

governor

pressure
15
is

considerably
high
the

valve
is

depressed
completely
toward

the

right
and
the

FSV
is

returned
to

the
Low

position
This

operation
is

called
Kick
down

shift

2nd
3rd
shift
valve
SSV

The
SSV
is

a
transfer
vaIve
which

shifts

speed
from
2nd
to
3rd

When
the
vehicle
is

stopped
the

SSV
is

depressed
toward
the

right
by
the

spring
and
is
in

the
2nd

position
It

is

provided
however
that
the
FSV

decides
the

shifting
either

to
Low

or

2nd

When
the

vehicle
is

running
the

governor

pressure
15
is

applied
to

the

right
end
surface
and
the
SSV
is

depressed
toward
the

left

Contrarily

the

spring
force
line

pressure
3
and

throttle

pressure
19

depress
the

SSV

toward
the

right

When
the

vehicle

speed
exceeds
a

certain
level
the

governor

pressure

exceeds
the
sum
of
the

spring
force

line

pressure
and
throttle

pressure
the

valve
is

depressed
toward
the
left
and

the
line

pressure
3
is
closed
Conse

quently
the
forces

are
rapidly
un

balanced
the
force
to

depress
the
SSV

toward
the

right
reduces
and
thus
the

SSV
is

depressed
to
the
Ie
ft
end

for
a

moment

With
the
SSV

depressed
to

ward
the

left
end
the
line

pressure
3

is

connected
with
the
line

pressure

10
the

band
servo
is
released
the

front
clutch
is

engaged
and

speed
is

shifted

to
3rd

When

the
accelerator

pedal
is

de

pressed
both
the
line

pressure
3

and

the
throttle

pressure
19

are

high
and
AUTOMATIC
TRANSMISSION

therefore
the

SSV
is

retained
in

2nd
unless
ihe

governor
pressure

IS
exceeds

the
line

pressure
3
and

the

throttle

pressure
19

In

the
3rd

position
force
to

depress
the

SSV
toward
the

right
is

remained

only
on
the
throttle

pressure

16
and

the
throttle

pressure
16
is

slightly
lower
than
that

toward
the

right
which
is

applied
while

shifting

from
2nd
to
3rd

Consequently
the
SSV
is
returned

to
the

2nd

position
at
a

slightly
low

speed
side

Shifting
from
3rd
to

2nd

occurs
at

a
speed

slightly
lower

than
that
for

2nd
to
3rd

shifting

When
kicked
down
at
the
3rd

line

pressure
13
is
led
from
the
SDV

and
the
SSV
is

depressed
toward
the

right
Although
the

governor
pressure

is

considerably
high
the
valve
is

de

pressed
completely
toward
the

right

and
thus
the
SSV
is
returned
to

2nd

position
This

operation
is

called
Kick
down
shift

When
the
shift
lever
is
shifted

to

2
or
I

range
at
the

3rd

speed

the
line

pressure
3
is

drained
at

the

MNV

Consequently
the
front
clutch

operating
and
band
servo

releasing
oils

are
drained
As

the

res
lIt
the
trans

mission
is
shifted

to
the
2nd
or

low

speed
although
the

SSV
is
in

the
3rd

position

When
the

speed
is
shifted
to
the

3rd
a

one

way
orifice
24
on
the

top
of
the

SSV
relieves
oil

transmitting

velocity
from
the
line

pressure
3

to

the
line

pressure
10
and
reduces
a

shock

generated
from
the

shifting

Contrarily
when
shifted
from
3rd

to
2
or

range
and
the

speed
is

shifted
to
the
2nd

spring
of
the
orifice
24
is

depressed
the
throttle

becomes
ineffective
the

line

pressure

10
is

drained

quickly
and
thus

delay
in
the

speed
shifting
is

elimi

nated

Throttle

of
the

line

pressure
6

relieves
the
oil

transmitting
velocity

from
the

line

pressure
6
to
the

line

pressure
10
when

the
lever
is

shifted

to
the

R

range
and
relieves
drain

velocity
from
the
line

pressure
10
to

the
line

pressure
6

when

shifting

from
3rd
to

2nd
at

the
D

range
Thus
the
throttle
of
the
line

pressure
6
reduces

a
shock

generated

from
the

shifting

A

plug
in
the
SSV
left

end

readjust

the
throttle

pressure
16
which
varie

depending
on
the

engine
throttle
con

dition
to
a

throttle

pressure
19

suited
to
the

speed
change
control

Moreover
the

plug
is

a
valve
which

applies
line

pressure
13
in

lieu
of
the

throttle

pressure
to
the

SSV
and
the

FSV
when
kick

down
is

performed

When
the
throttle

pressure
16
is

applied
to
the
left
side
of
this

plug

and
the

plug
is

depressed
toward
the

right
a
slight

space
is
made
from
the

throttle

pressure
16
to

19
A
throt

tIe

pressure
19
which
is
lower

by
the

pressure
loss

equivalent
to
this

space
is

generated
the

pressure
loss
is
added
to

the

spring
force
and
thus

the

plug
is

depressed
back
from
the

right
to
the

left

When
this

pressure
19
increases

excessively
the

plug
is
further
de

pressed
toward
the
left

space
from

the

throttle

pressure
19
to
the
drain

circuit

13
increases
and
the
throttle

pressure
19
lowers
Thus
the

plug
is

balanced
and
the

throttle

pressure

19
is
reduced
in
a

certain
value
b

3
Orifice

t

checking
valve

24

15

2
2

i
I

1
c

V
Y
ii
pr

W
jt1

iff
I
W
q

I
nHH

J

L19
H
10

15

AT
9
A

T098

Fig
AT

13
2nd
3rd

shiflvalue

against
the

throttle

pressure
16

When

performing
the

kick
down

the

SOV

moves
a

high
line

pressure
is

led
to

the
circuit
19

from
the
line

pressute
circuit
13

which
had

been

drained
the

plug
is

depressed
toward

the
left

and
the
circuit

19
becomes

equal
to
the

line

pressure
13
Thus

the

kick
down
is

performed

Preasure
modifier
valve

PMV

In

comparison
with
the

operating

pressure
required
in

starting
the

vehi

ele

power

transmitting
capacity
of
the

clutch

in
other

words

required
op

erating
pressure
may
be

lower
when

the

vehicle
is
once

started
When
the

line

pressure
is
retained
in

a

high
level

up
to
a

high
vehicle

speed
a
shock

generated
from
the

shifting
increases

and
the
oil

pump
loss
also

increases
In

order
to

prevent
the
above

described

defective
occurrences
with

the

opera

lion

of
the

governor
pressure
15
the

throttle

pressure
must
be

changed
over

to

reduce
the

line

pressure
The
PMV

is
used

for
this

purpose

When
the

governor

pressure
15

which
is

applied
to

the

right
side
of

the

PMV
is

low
the
valve
is

depressed

toward

the

right
by
the

throttle

pres

sure

16

applied
to

the
area

differ

ence
of

the
value
and
the

spring
force

and

the
circuit

from
the

circuit
16
to

the

circuit
18
is

closed

However

when

the

vehicle

speed
increases
and

the

governor

pressure
15
exceeds
a

certain

level
the

governor

pressure

toward

the
left

which
is

applied
to
the

right
side

exceeds
the

spring
force
and

the

throttle

pressure
16
toward
the

right
the
valve
is

depressed
toward
the

left
and
the

throttle

pressure
is

led

from
the
circuit

16
to

the

circuit

18
This

throttle

pressure
18
is

applied
to

the

top
of
the

PRY

and

pressure
of
the
line

pressure
source
7

is

reduced

Contrarily
when
the
vehi

cle

speed
lowers
and
the

governor

pressure
15
lowers
the

force
toward

the

right
exceeds
the

governor
pres
CHASSIS

sure
the
valve
is

depressed
back
to

ward
the

right
the

throttle

pressure

18
is
drained
to

the

spring
unit

This

valve
is

switched
when
the

throttle

pressure
and
the

governor

pressure
are

high
or
when

the
throttle

pressure
is

low
and
the

governor

pres

sure
is
low

II

18
16

1JU

k
I

15

AT099

Fig
AT
14
Pressure

modifier
valve

Vacuum
throttle
valve

VTV

The

vacuum

throttle
valve
is
a

regulator
valve

which
uses

the
line

pressure
7
for
the

pressure
source

and

regulates
the

throttle

pressure
16

which

is

proportioned
to
the

force

of

the

vacuum

diaphragm
The

vacuum

diaphragm
varies

depending
on
the

engine
throttle
condition

negative

pressure
in
the

intake
line

When
the
line

pressure
7
is

ap

plied
to

the
bottom

through
the
valve

hole

and
the

valve
is

depressed

up

ward

space
from
the

line

pressure
7

to
the

throttle

pressure
16
is

closed

and
the

space
from
the

throttle

pres

sure

16
to
the

drain
circuit
17
is

about
to

open
In

this

the
throttle

pressure
16
becomes
lower

than
the

line

pressure
7

by
the

pressure

equivalent
to
the

pressure
loss

of
the

space
and
the

force
to

depress

through
the

rod
of
the

vacuum

dia

phragm
is

balanced
with
the

throttle

pressure
16

applied
upward
to

the

bottom

When

the

engine
torque
is

high
the

negative
pressure
in
the

intake

line

rises

similar
to
the

atmospheric
pres

sure
and
the

force
of

the
rod
to

depress
the
valve

increases

As
the

result
the
valve
is

depressed
down

ward
the

space
from
the
throttle

pressure
16
to

the
drain

17
re

AT

lO
duces
and
the

space
from
the

line

pressure
7
to
the

throttle

pressure

16
increases

Consequently
the

throttle

pressure

16
increases

and
the

valve
is

baI

anced

Contrarily
when

the

engine

torque
lowers
and
the

negative
pres

sure
in

the
intake
line
lowers

similar

to
vacuum
force
of

the
rod

to
de

press
the

valve
lowers
and
the

throttle

pressure

16
also

lowers

When
a

pressure
regulated
by
the
throttle

back

up
valve
described
in

the
subse

quent

paragraph
is

led

to
the
circuit

17
a

high

pressure
is

applied

through

the

space
from
the
circuit
17

to
the

throttle

pressure
16

Consequently

the
VTV
is

unbalanced
the

throttle

pressure
16
becomes

equal
to

the

back

up
ptessure
17
and
the
valve
is

locked

upward

bi

II
I

ATlOa

Fig
AT
15
Vacuum

throttle

valve

Throttle

back

up
valve
TBV

Usually
this
valve
is

depressed

downward

by
the

spring
force

and
the

circuit

17
is

drained

upward

As

soon
as
the
lever
is

shfted
either

to
2
or

range
line

pressure
is

led

from
the
circuit
4

the
line

pressure
is

applied
to
the
area
differ

ence
of
the
valve

the
valve
is

depres

sed

upward
the

space
from
the
circuit

CHASSIS

1

range
Low

gear

When

starting
in
I

range
the

driving
gear
is
locked
to
the
low

gear

ratIO

In
1

range
the

reaT
dutch

is

applied
and
the
low
and
reverse
brake

holds
the

connecting
drum
and

rear

planet
carrier
from

rotating
The

power
flow
takes

place
through
the

input
shaft
and
into
the
rear
dutch

Rotation

of
the
rear
clutch
drives
the

rear
clutch
hub

and
front
internal

gear

The
front
internal

gear
rotates
the

front

planetary
gears
clockwise
to

cause

the
sun

gear
to
rotate
counter

clockwise

Counterclockwise
rotation
of
the

sun

gear
turns
the
rear

planetary
gear

clockwise

The
rear

planet
carrier

splined
to

the

connecting
drum
is
held
from

rotating
by
the
low
and

reverse
brake

The
clockwise
rotation
of
the
rear

planetary
gears
therefore
rotates
the

rear
internal

gear
and

internal
drive

tlange
The

internal
drive

tlange
is

splined
to
the

output
shaft
and
rotates

the

output
shaft
clockwise
However

the

output
shaft
rotates
at
a

lower

speed
compared
with
that
of
the

input

shaft
This
is

caused

by
the
fact
that

the
front

planet
carrier
rotates
at
the

same

speed
as

the

output
shaft
in
the

same
direction
since
the
carrier
is

splined
to

the

output
shaft
The

front

internal

gear
and

planetary

gear
as

sembly
are

rotating
in
the

same
direc

tion
but
the

planet
carrier
is

rotating

at

a

speed
slower
than
the

ring
gear
So

the

gear
ratio

of
this

speed
range
is
a

combination
of
the
ratios

provided
by

the
front
and

rear

planetary
gear
a

semblies

When

the
manual
valve

CV
is

posi

tioned
at
I
the
line

pressure
7
is

applied
into
the

line

pressure
circuits

I
4
and
5
The

oil

pressure
in
5

actuates
the

low
and

reverse
brake

after

being
introduced
into

the
circuit

12

through
the

lst
2nd
shift
valve

@
and

the
line

pressure
I

acts
on
i

C

AT076

Fig
A
T

43
Power
transmission

during
11

range

A

Ton

Fig
A

T
44

Operation
of
each
mechanism

during
11
range

Clutch
Low

Band
rvo
On

Parking

Range
Gm

ratio
reverse
w

pawl

Front

Rear

brake
Operation
Release

clutch

Park
on
on

Reverse
2
182
on
on
on

Neutral

DI
low
2
458
on
on

Drive
D2
Second
1
458
on
on

D

Top
1
000
on
on
on
on

2
Second
1
458
on
on

12
Second
1
458
on
on

I

Low
2
458
on
on

the

rear
clutch
and

governor
The
line

pressure
4
acts
in

the
same
manner
as

in
2

range

Similar
10
that
of
the
D

range

the
line

pressure
increases
with
the

degree
of

depressiun
of
the
accelerator

pedal
and
the
line

pressure
decreases

with
the
increase
of

car

speed
The
governor
pressure
IS
which
acts
on

the
Ist
2nd

shift
valve
does

not

increase
until

it
overcomes
the
com

bined

force
of
the

line

pressure
12

and
the

spring

causing
nu
I

st
2nd

speed

change

AT
3D

AUTOMATIC
TRANSMISSIO
N

TROUBLE
DIAGNOSES
AND
ADJUSTMENT

INSPECTION
AND
ADJUSTMENT

BEFORE
TROUBLE
DIAGNOSIS

Testing
instrument
for

inspection

Checking
oil
level

Inspection
and

repair
of
oil

leakage

Checking
engine

idling
rpm

Checking
and

adjusting
kick
down
switch

and
downshift
solenoid

Inspection
and

adjustment
of
manual

linkage

Checking
and

adjusting
inhibitor
switch

STALL
TEST

Stall

test

procedures

Judgement

As
the
troubles
on

the
automatic

transmission
can
be

mostly
repaired
by

doing
simple
adjustment
so
do

not

disassemble

immediately
if
the

auto

m
tic
transmission
is
in
trouble

Firstly
inspect
and

adjust
the
auto

matic
transmission
with

mounting
on

vehicle

by
observing
the

trouble

shooting
chart

If
the

trouble
could
not
be

solved

by
this

procedure
then

remove
and

disassemble
the
automatic
transmis

sion
It

is
advisable
to
check

overhaul

and

repair
each

point
in
the

order

itemized
in

the
trouble

shooting

chart

l
In
the

trouble

shooting
chart

the

diagnosis
items

are

arranged
in
the

order
from

easy
to

difficult
and
there

fore

please
follow
these
items

The

transmission
should
not
be
removed

unless

necessary

2
The

test
and

adjustment
for
trou

ble

diagnosis
should
be
made

on
the

basis
of
standard
values
and
the
data

should
be
recorded
ROAD
TEST

Car

speed
at

gear
shift

Checking
speed

changing
condition

Checking
items

during
speed
change

Shift
schedule

LINE
PRESSURE
TEST

Line

pressure
governor
feed

pressure

Judgement
in

measuring
line

pressure

TROUBLE
SHOOTING
CHART

Inspecting
items

Trouble

shooting
chart
for
3N71
B
Automatic

Transmission

Trouble

shooting
guide
for
3N718
Automatic

Transmission
CONTENTS

AT
49

AT
49

AT
49

AT
50

AT
50

AT
50

AT
51

AT
51

AT
51

AT51

AT
52

INSPECTION
AND

AD
JUSTMENT

BEFORE

TROUBLE

DIAGNOSIS

Testing
instrument
for

inspection

1

Engine
tachometer

2
Vacuum

gauge

3
Oil

pressure
gauge

It

is
convenient
to

install
these

instruments
in
a

way
that
allows

meas

urements
to
be
made

from
the
driver
s

seat

Checking
oil

level

In

checking
the
automatic
transmis

sion
the
oil

level
and

the
condition
of

oil
around

the
oil
level

gauge
should
be

examined

every
5

000
km
3
000

miles
These

steps
are

easy
and

effec

live

in
trouble

shooting
as
some

change
of
oil
conditions
are

linked

with

developed
troubles
in

many
cases

AT
49
AT
52

AT
52

AT
53

AT
53

AT
53

AT
53

AT
53

AT
54

AT
54

AT
54

AT
55

AT
5B

For
instance

Lack

of
oil
causes
defective

opera

tion

by
making
the
clutches
and

brakes

slip
developing
severe

wear

The

cause
of

this

operation
is
that

the

oil

pump
has

begun
to

suck
air

which

caused
oil

foaming
thus

rapidly

deteriora

ting
the
oil

quality
and

pro

ducing
sludge
and

varnish

Meanwhile
excessive
oil
is
also
bad

as
in
the

case
of

a
lack

of
oil
because

of
oil

foaming
by
being
stirred

up
by

the

gears
Moreover
in

high
speed

driving
with
excessive
oil
in
the
trans

mission
the
oil

often
blows
out
from

the
breather

I

Measuring
oil
level

When

checking
the
fluid
level
start

the

engine
and
run
it
until
normal

operating
temperatures
oil

tempera

ture
50
to

800e
122
to
176
F

Approximately
ten
minute

operation

will
elevate
the

temperature
to
this

range
and

enigne
idling
conditions

are
stabilized
Then

apply
the
brakes

and
move
the
transmission

shift
lever

Checking
speed

changing

condition

The

driver
s

feeling
during
gear

changes
should
also
be

checked
at

tentively

1
A

sharp
shock
or
unsmoothness

are
felt

during
a

gear
change

2

A

gear
change
is
made
with
a

long

and

dragging
feeling

These
indicate

that
the
throttle

pressure
is
too
low
or

some
valve

connected
to
the
throttle
is
defective

Checking
items

during

speed
change

1
In
D

range
gear
changes
DI
o

D2

D3
are
effected
In
R

range

the

speed
does

not
increase

2

The
kick
down

operates
properly

3

By
moving
the
lever
from
D

into
I

gear

changes

D3
2
12

II
are

effected
In
the

ranges
12

and

II
the

engine
braking
works

properly

4
In
the

speed
does
not
in

crease

5
Should
be

quickly
fixed
at
2

range

6
In
P

vehicle
can
be

parked

properly

If

any
malfunction
occurs
in
the

second

gear
during
the
road
test
that

is
if

vehicle
shakes

drags
or

sling
in

shifting
up
from

DI
directly
to

D3
or
in

shifting
up
from
D
to
W
I

r

I

1

1

I
2
31

I

I

I

I

I

t

Lh

I

I

I

I

1000
lsOo

2000
2500

Output
shaft

speed
rpm
AUTOMATIC
TRANSMISSION

D2
the

brake

band
should
be
ad

justed
If

these

troubles
remain

after

Shift

schedule

o

Full
throttlell

e

2100

E
E

200

is

Z

cu

300

mmHg

soo

o

soo

LINE

PRESSURE
TEST

When

any

slipping
occurs
in

clutch

or
brake
or

the

feeling
during
a

speed

change
is

not

correct
the
line

pressure

must
be
checked

Measuring
the
line

pressure
is

done

by
a

pressu
re

gauge
attached
to

two

pressure

measuring
holes
after

re

moving
blind

plugs
located
at

trans

mission

case
See

Figure
AT

112

The

line

pressure
measurement

is

begun
at

idling
and

taken

step
by

step

by

enlarging
the
throttle

opening

1
A

sharp
shock
in

up

shifting
or

too

high

changing
speeds
are
caused

mostly
by
too

high
throttle

pressure

2

Slipping
or

incapability
of

opera

Line

pressure
governor
feed

pressure

At
cut

back

point
After
cut
back

Throttle

opening
under

approximately
over

approximately

15

kmfh
9

MPH
35

kmfh
22
MPH

Unit

mmHg
Unit

kg
cm2

psi
Unit

kg
cm2

psi

Full
throttle

0
94
to
11
0

134
to
156
5
5

to
6
5

78
to

92

Minimum
throttle
450
3
0

to
4
0
43

to
57
3

0
to
4
0
43

to
57

Full
throttle
0
10
0
to
12

0

142
to

171
5
5

to
7
0

78
to
100

Minimum

throttle
450

6
0
to

12
0
85toI71
5
5
to
7
0

78
to

100

Full
throttle
0

14

0
to
16

0

199
to

228
14
0

to
16
0

199
to
228

Minimum

throttle
450

3

0
to
5
5

4310
78
3

0
to
5
5

43
to
78
Range

D

2

R
the
brake
band
is

adjusted
check

the

servo

piston
seal
for
oil

leakage

3

30ixI
3500
000

AT110

Fig
A
T

llI

Shift
schedule

tion
is

mostly
due
to
oil

pressure

leakage
within

the

gear
trains
or

spool

valve

AT113

I

Line

pressure

2

Governor
reed

3

Servo
release

pressure

Fig
A
T
112

MeCJ8uring
line

pressure

Notes
a
The
line

pressure
during

idling
corresponds
to

the
oil

pressure
before

cut
down

at
minimum

throttle

b
The
oil

pressure
After
cut
back
means

that
after
the

pressure
modifier

valve
has

operated

AT
53